The acoustic energy generated by rotating moving mechanical parts together with their bearings is transmitted in the form of airborne and structure-borne noise by the housing in which these mechanical elements are accommodated. In this process, some of this acoustic energy is directly transmitted as airborne acoustic energy, whereas the remainder, which is usually the greater part, is transmitted through the structure to the foundation supports of the mechanical assembly concerned. This structure-borne acoustic energy generates airborne acoustic energy in turn, as it is transmitted from the floor into the room.
The application of continuously more severe regulations aimed at restricting noise levels have obliged machinery designers to adopt designs characterized by especially efficient soundproofing.
The following methods of soundproofing are known to practitioners of the state of the art:
Friction soundproofing at the interfaces or mating faces of the various components, resulting in an increase of the transitional resistance; PA1 Supplementary soundproofing of moving mechanical parts as well as of the walls of housings by the application of one or several coatings of soundproofing material, such as sound deadening or sandwich materials, by lining particular recesses and hollow spaces with soundproofing material as well as by the use of special vibration absorbers; PA1 Internal or frictional soundproofing of the materials themselves, which is not applicable to metal components.
Ways are known of enhancing the dynamic rigidity of components by adopting thick-wall designs, thus providing a dimensionally and vibrationally stable structure whose energy flow paths are as short as possible.
The purpose of the present invention is to provide a simple way of effectively improving soundproofing.